Method for evaluating quality of quicklime powder and deducting tonnage according to detection result

Abstract

The invention discloses a method for evaluating the quality of quicklime powder and deducting tons according to a detection result, and belongs to the field of metallurgical quicklime powder detection. Comprising the steps of material receiving and butt joint; samples are collected in one vehicle, and the total amount is not lower than a preset standard; particle size screening operation is carried out, and whether tonnage deduction operation is carried out or not is judged based on the undersize product proportion; carrying out a digestion test, and rapidly judging an activity index by monitoring digestion time; detecting impurities, and determining the content of the impurities according to the proportion of the washed and separated residues; carrying out a heating test, and determining an activity index by monitoring the time of reaching a specified temperature; and performing tonnage deduction comprehensive calculation according to the tonnage deduction standard corresponding to each detection result and the multiple determined by the tank truck loading net weight. According to the method, quick evaluation of the quality of the quick lime on site is realized, the defect of lagging of test components is overcome, quantitative management of the quality of the quick lime powder is realized through a clear detection means and a ton deduction standard, and the stability of the quality of sintered ore is guaranteed.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical quicklime powder testing technology, and particularly relates to a method for evaluating the quality of quicklime powder and deducting tonnage based on the test results. Background Technology

[0002] In the metallurgical industry, quicklime powder is a crucial flux material in the sintering process, and its quality directly affects the stability of the final sinter. Currently, in industrial production, quicklime powder is typically transported to the plant via lime tanker trucks and directly piped into quicklime powder silos for use. While this transportation and usage model offers advantages in logistical efficiency, it poses challenges to raw material quality control and rapid feedback in actual production operations.

[0003] However, existing technologies have significant drawbacks, primarily in their insufficient ability to rapidly assess the quality of quicklime powder. Specifically, the chemical analysis of incoming quicklime powder often exhibits a lag, making it difficult to quickly and accurately determine whether its quality meets the process requirements of sintering production before its use. Using substandard quicklime powder can lead to a series of serious quality issues, including but not limited to unstable sinter quality and reduced sinter basicity. Therefore, the industry urgently needs a method for rapidly verifying quicklime powder quality on-site, enabling operators to take timely and necessary measures to effectively ensure the quality of sintered products. Summary of the Invention

[0004] To address the problem that existing technologies often lag in the analysis of quicklime powder composition, making it difficult to quickly and accurately determine whether its quality meets requirements before it is put into use, this invention provides a method for evaluating the quality of quicklime powder and deducting tonnage based on the test results.

[0005] This invention is implemented as follows: a method for evaluating the quality of quicklime powder and deducting tonnage based on test results, characterized by comprising the following steps: S1. Receiving and docking: After the material is deemed qualified, dock the tanker truck with the ash discharge pipeline; S2. Sample collection: After docking is completed, operate the sampling equipment to collect a representative quicklime powder sample; S3. Particle size detection: The sample is sieved to determine whether to deduct impurities based on the difference between the sieve results and the preset particle size standard. S4. Digestibility test: The sample is subjected to a digestion test. The digestibility index of quicklime powder is determined by monitoring the digestion reaction time, and the digestion deduction ton is determined according to the digestibility deduction ton standard. S5. Impurity content detection: After the digestion test, the sample is washed and separated, the content of insoluble residue in the sample is determined, and the impurity deduction amount is determined according to the impurity content deduction standard. S6. Temperature-increasing activity test: The sample is subjected to a temperature-increasing test. The water activity index of quicklime powder is determined by monitoring the temperature-increasing rate of reaction with water or the time to reach the specified temperature. The deduction amount for temperature-increasing activity is determined according to the standard for deducting tons based on temperature-increasing activity. S7. Comprehensive calculation after deducting tonnage: The corresponding deduction factor is determined based on the difference between the net weight of the tanker and the preset loading base; the deduction factors for digestion, impurities, and heating are combined and multiplied by the deduction factor to obtain the total tonnage to be deducted.

[0006] In the above technical solution, preferably, the particle size sieving specifically involves: taking a quantitative sample from the sample and sieving it using a round mesh sieve of a specified specification; if the proportion of the undersize material is lower than a preset threshold, then impurity deduction is performed.

[0007] In the above technical solution, preferably, the digestion test includes: placing a quantitative sample into a container, adding an appropriate amount of water, monitoring the total time from the start of the hydration reaction to the end of the reaction, and stirring the sample during the reaction process a specified number of times and for a specified duration.

[0008] In the above technical solution, preferably, the digestion activity deduction standard is based on the graded comparison relationship between the digestion reaction time and the preset time interval. The longer the digestion time, the higher the determined digestion deduction.

[0009] In the above technical solution, preferably, the step of detecting impurities includes: rinsing the digested sample and the sieve together in water, separating the non-dripping residue, weighing it, and calculating the mass ratio of the residue to the total sample.

[0010] In the above technical solution, preferably, the impurity content deduction standard is based on the graded comparison relationship between the proportion of residue and the preset proportion range. The higher the proportion of impurities, the higher the determined impurity deduction in tons.

[0011] In the above technical solution, preferably, the heating test includes: adding a quantitative sample to a beaker containing a fixed amount of water at a constant temperature, and timing the time required for the sample and water to reach a specified target temperature after mixing.

[0012] In the above technical solution, preferably, the heating activation ton standard is based on the deviation of the time required to reach the specified target temperature from a preset time benchmark. The longer the time or the failure to reach the target temperature, the higher the determined heating ton standard.

[0013] In the above technical solution, preferably, in the comprehensive calculation of the tonnage deduction, the comprehensive superposition method is: to simply add up the digestion deduction tonnage, the impurity deduction tonnage, and the heating deduction tonnage to obtain the basic deduction tonnage.

[0014] In the above technical solution, preferably, the particle size detection step specifically includes: if the proportion of undersize material obtained after particle size sieving is lower than a preset threshold, then the particle size of the quicklime powder is determined to be unqualified, and the impurity detection operation in step S5 is performed to determine the impurity deduction amount based on the impurity content deduction standard.

[0015] The method provided by this invention enables rapid on-site evaluation of the quality of incoming quicklime powder, effectively overcoming the shortcomings of traditional, delayed component analysis. This allows for timely detection and handling of quality issues, preventing potential quality problems in subsequent projects caused by the use of substandard quicklime powder. Through clearly defined testing methods and tonnage deduction standards, this method achieves quantitative management of quicklime powder quality, resulting in more scientific and accurate quality evaluations and contributing to the stability of project quality. Furthermore, this invention includes special handling measures, ensuring the standardization and safety of testing operations under abnormal conditions and reducing the risk of testing errors and safety accidents caused by equipment failure or improper operation. The tonnage deduction standard, which comprehensively considers the vehicle's load weight, makes the final tonnage deduction result more reasonable. This not only protects the legitimate rights and interests of suppliers but also effectively encourages them to provide higher-quality quicklime powder. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0017] This invention provides a method for evaluating the quality of quicklime powder and deducting tonnage based on test results. To further illustrate the structure of this invention, a detailed description is provided below: Example 1 A method for evaluating the quality of quicklime powder and deducting tonnage based on test results includes the following steps: Material Receiving and Connection: Receiving personnel must be strictly confirmed by sintering staff before contacting the tank truck and quicklime powder pipeline for connection. This step ensures the standardization and safety of the connection operation. Receiving personnel must undergo professional training to ensure they have a full understanding of the sintering process and quicklime powder quality standards, enabling them to conduct the first on-site verification of incoming materials and improve the quality control at the source of material receiving.

[0018] Sample Collection: After the tanker truck docking is completed, the receiving personnel operate the sampling equipment, i.e., the sampling machine, to collect representative quicklime powder samples. Each sample is identical to the previous one, and the total weight of each sample is no less than 8 kg. The sampling machine should collect sub-samples from multiple evenly distributed locations within the tanker truck during unloading or at different points, then mix them to form a representative sample of at least 8 kg. This multi-point sampling mechanism ensures that the samples accurately represent the quality of the entire truckload of goods, effectively avoiding potential localized falsification by suppliers and improving the impartiality of the test results.

[0019] Particle size analysis: The sample was sieved for particle size distribution. Specifically, 1 kg of a quantitative sample was taken and sieved using a 3mm round-mesh sieve. The sieve results showed that the proportion of material passing through the sieve was 88%. Since this proportion is below the preset threshold of 90%, the impurity deduction standard was applied. This rapid particle size analysis allows for quick on-site assessment of the sintering degree and crushing quality of quicklime powder, reducing the failure rate of subsequent experiments and saving testing costs and time.

[0020] Digestion Activity Test: A digestion test was performed on the sample. The specific procedure was as follows: Take 1 kg of quantitative sample and place it in a container in a cone shape. Add approximately 250 ml of water to the deep center. Start timing after adding water. Stir for 15 seconds at 60 seconds and 90 seconds respectively, until the reaction stops producing white smoke, the ash becomes powdery, and it does not clump. In this example, the monitored digestion reaction time was 135 seconds. According to the standard for deducting tonnes based on digestion activity (1 tonnes deducted for 131 to 140 seconds), the deduction for digestion was determined to be 1 ton. This test, through the intuitive exothermic hydration reaction time, reflects the rate at which CaO in quicklime is converted to Ca(OH)2. It is the most effective means of judging the quality of quicklime on-site, and can quickly identify and prevent the use of quicklime powder with excessively low activity or overburnt quicklime powder.

[0021] Impurity content detection: The sample after digestion is rinsed and separated. The specific procedure is as follows: The digested sample, along with the sieve, is repeatedly rinsed in water until no white slurry is produced in the residue. After draining until no water drips, the residue is weighed, and the proportion of residue is calculated. In this example, the content of insoluble residue (impurities) was determined to be 43%. Based on the impurity content deduction standard (41% to 45% deducts 1 ton), the deduction amount for impurities is determined to be 1 ton. This method removes soluble components through wet sieving, retaining only water-insoluble impurities (such as quartz, unburned fuel residue, etc.), achieving physical separation and accurate measurement of impurities, avoiding the lag of traditional chemical analysis.

[0022] Temperature-increasing activity test: A temperature-increasing test was conducted on the sample to determine the water activity index of quicklime powder. The specific procedure was as follows: 600 ml of constant-temperature water (20℃±2℃ indoors in summer or 16℃±2℃ indoors in winter) was poured into a beaker, and a thermometer at 28℃ was placed inside. 150 g of quantitative sample (quicklime powder) was added, and the time required to heat to 90℃ was measured. In this example, the required time was 105 seconds. Based on the temperature-increasing activity deduction standard (90 seconds as the baseline, 1 ton deducted for every 101 to 110 seconds), the deduction for temperature increase was determined to be 1 ton. This test, by quantifying the exothermic rate, provides a more accurate activity index, compensating for the shortcomings of digestion tests that only focus on the endpoint time. The results can be directly used to guide the fine-tuning of flux dosage in the sintering batching system.

[0023] Comprehensive calculation of tonnage deduction: First, determine the multiplier: The net weight of the tanker is 45 tons. Based on the preset loading base (40 tons), its net weight falls within the range of 40T to 60T, therefore the corresponding tonnage deduction multiplier is determined to be 1.5. Second, comprehensive calculation: Simply add up the tonnage deduction for digestion (1 ton), impurities (1 ton), and temperature increase (1 ton) to obtain a basic tonnage deduction of 3 tons. Finally, calculate the total tonnage to be deducted: (1+1+1)*1.5=4.5 tons. This comprehensive calculation method of adding up and multiplying by a multiplier fully reflects the fairness and rationality of the penalty, not only deducting tonnage for quality defects but also imposing additional penalties on overloaded transportation, thus incentivizing suppliers to adopt more standardized transportation and loading methods.

[0024] Example 2 Quality evaluation and tonnage deduction for quicklime powder with a net load weight less than the base weight This embodiment aims to demonstrate the calculation of tonnage deduction under different quality indicators when the net weight of the tanker truck is within the base value.

[0025] Material receiving and docking, and sample collection: Complete the material receiving, docking, and sample collection operations according to the steps and procedures described in the example. The total amount of representative quicklime powder sample collected in this example is 8.2 kg.

[0026] Particle size analysis: The quantitative sample was sieved, and the sieve results showed that the proportion of undersize material was 92%. This proportion meets the requirements, therefore no additional impurity deduction is triggered. This result indicates that the physical properties of quicklime powder meet the requirements of sintering production, ensuring the permeability of the material layer and indirectly reducing fuel consumption during the sintering process.

[0027] Digestion activity test: A digestion test was conducted on a quantitative sample, and the digestion reaction time was monitored at 175 seconds. Based on the standard deduction for digestion activity (3 tons deducted for 171 to 180 seconds), the deduction was determined to be 3 tons. This result indicates that the quicklime powder of this batch has poor activity; timely detection and deduction can effectively avoid the potential risks of decreased basicity and unstable quality of the sintered ore.

[0028] Impurity content detection: The sample after the digestion test was washed, separated, and weighed. The content of insoluble residue (impurities) was determined to be 38%. Based on the impurity content deduction standard (0.5 tons deducted for 35% to 40%), the impurity deduction was determined to be 0.5 tons. This low impurity deduction reflects the high purity of quicklime, which has a positive impact on flux consumption and slag volume in the subsequent sintering process.

[0029] Temperature rise activity test: A temperature rise test was conducted on a quantitative sample, and the time required to heat to 90℃ was measured to be 118 seconds. Based on the temperature rise activity deduction standard (1.5 tons deducted for every 111 to 120 seconds), the deduction for temperature rise was determined to be 1.5 tons. This test result complements the digestion test result, providing sintering engineers with dual activity verification, greatly enhancing the scientific rigor and accuracy of quicklime powder quality evaluation.

[0030] Comprehensive calculation of tonnage deduction: First, determine the multiplier: The net weight of the tanker is 38 tons. Based on the preset loading base (40 tons), its net weight is less than 40 tons, therefore, normal tonnage deduction (deduction multiplier is 1) is applied. Second, comprehensive calculation: Simply add up the tonnage deduction for digestion (3 tons), impurities (0.5 tons), and temperature increase (1.5 tons). The total tonnage to be deducted is 3 + 0.5 + 1.5 = 5 tons. This method can quantitatively evaluate the quality of quicklime powder, making up for the shortcomings of traditional laboratory component analysis, and achieving timely and effective quality control.

[0031] Special Circumstances Handling: During normal dust collection, the sampling equipment must be in automatic mode. If low air pressure or equipment malfunction prevents normal sample collection, dust collection should be stopped immediately and the dispatcher notified. If manual sampling is required before the equipment is repaired, relevant personnel must be present before operation; manual sampling by the material pipe alone is strictly prohibited. This procedure ensures the standardization and safety of testing operations under abnormal conditions, reduces testing errors and safety accidents caused by equipment failure or improper operation, and ensures data reliability.

[0032] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for evaluating the quality of quicklime powder and deducting tonnage based on test results, characterized in that, Includes the following steps: S1. Receiving and docking: After the material is deemed qualified, dock the tanker truck with the ash discharge pipeline; S2. Sample collection: After docking is completed, operate the sampling equipment to collect a representative quicklime powder sample; S3. Particle size detection: The sample is sieved to determine whether to deduct impurities based on the difference between the sieve results and the preset particle size standard. S4. Digestibility test: The sample is subjected to a digestion test. The digestibility index of quicklime powder is determined by monitoring the digestion reaction time, and the digestion deduction ton is determined according to the digestibility deduction ton standard. S5. Impurity content detection: After the digestion test, the sample is washed and separated, the content of insoluble residue in the sample is determined, and the impurity deduction amount is determined according to the impurity content deduction standard. S6. Temperature-increasing activity test: The sample is subjected to a temperature-increasing test. The water activity index of quicklime powder is determined by monitoring the temperature-increasing rate of reaction with water or the time to reach the specified temperature. The deduction amount for temperature-increasing activity is determined according to the standard for deducting tons based on temperature-increasing activity. S7. Comprehensive calculation after deducting tonnage: The corresponding deduction factor is determined based on the difference between the net weight of the tanker and the preset loading base; the deduction factors for digestion, impurities, and heating are combined and multiplied by the deduction factor to obtain the total tonnage to be deducted.

2. The method according to claim 1, characterized in that, The particle size sieving process specifically involves taking a quantitative sample from the sample and sieving it using a round mesh sieve of a specified specification. If the proportion of the material passing through the sieve is lower than a preset threshold, then impurity deduction is performed.

3. The method according to claim 1, characterized in that, The digestion test includes: placing a quantitative sample into a container, adding an appropriate amount of water, monitoring the total time from the start of the hydration reaction to the end of the reaction, and stirring the sample a specified number of times and for a specified duration during the reaction process.

4. The method according to claim 1, characterized in that, The digestion activity deduction standard is based on the graded comparison relationship between digestion reaction time and preset time interval. The longer the digestion time, the higher the determined digestion deduction.

5. The method according to claim 1, characterized in that, The impurity detection step includes: rinsing the digested sample and sieve together in water, separating the non-dripping residue, weighing it, and calculating the mass ratio of the residue to the total sample.

6. The method according to claim 1, characterized in that, The impurity content deduction standard is based on the graded comparison relationship between the proportion of residue and the preset proportion range. The higher the proportion of impurities, the higher the determined impurity deduction in tons.

7. The method according to claim 1, characterized in that, The temperature rise test includes: adding a quantitative sample to a beaker containing a fixed amount of water at a constant temperature, and timing the time required for the sample and water to reach a specified target temperature after mixing.

8. The method according to claim 1, characterized in that, The heating activation tonne deduction standard is based on the degree of deviation between the time required to reach the specified target temperature and the preset time benchmark. The longer the time or the failure to reach the target temperature, the higher the determined heating activation tonne deduction.

9. The method according to claim 1, characterized in that, In the comprehensive calculation of the tonnage deduction, the comprehensive superposition method is to simply add up the tonnage deduction for digestion, the tonnage deduction for impurities, and the tonnage deduction for temperature increase to obtain the basic tonnage deduction.

10. The method according to claim 1, characterized in that, The particle size detection step specifically includes: if the proportion of undersize material obtained after particle size sieving is lower than a preset threshold, the particle size of the quicklime powder is determined to be unqualified, and the impurity detection operation in step S5 is performed to determine the impurity deduction amount based on the impurity content deduction standard.